Head choice for a 509 with iron heads
#21
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Joined: Mar 2012
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From: Cape coral, FL
I'm saltwater and went with iron heads also. The big question I think is what you believe will be gained by going aluminum over iron. You'll save a few pounds but the material doesn't determine how heads flow. I may have missed it but what's your cam specs? Compression?
#24
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Joined: Jun 2009
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From: Chicago
I didn`t say throw a blower on it .
You asked what people are using and I told you . Iron heads but that doesn`t matter if the timing is too low and the AFR`s are too lean.
Granted I don`t know much about N/A tuning in a light boat but I had a pair of Tyler Crocket 509s in a 33OL and they were no where near 14 at cruise. If I recall closer to 12.5
You asked what people are using and I told you . Iron heads but that doesn`t matter if the timing is too low and the AFR`s are too lean.
Granted I don`t know much about N/A tuning in a light boat but I had a pair of Tyler Crocket 509s in a 33OL and they were no where near 14 at cruise. If I recall closer to 12.5
Last edited by ICDEDPPL; 07-18-2017 at 10:39 PM.
#25
only real advantage of having aluminum over iron heads is the ability to fix them if something happens and ease of porting as aluminum is softer.
650-690 hp? the most I see in a 509 N/A would be 620-630 unless you really have a perfect parts selection, I would not go more then 310CC runner and do not buy heads done unless they are done by the shop putting engine together, always buy bare and have the builder make heads right.
14:1 at cruise? that's awful lean you may need to address carb and even that out, you should not fluctuate air foes that much from 1500-6000 I am high 11's to 12.4 the whole time.
buddy did builds with 502's, edelbrock ZZ502 heads fully ported, 238/246 cam and 850 carbs did 621HP you can make nice numbers if you chose parts right.
650-690 hp? the most I see in a 509 N/A would be 620-630 unless you really have a perfect parts selection, I would not go more then 310CC runner and do not buy heads done unless they are done by the shop putting engine together, always buy bare and have the builder make heads right.
14:1 at cruise? that's awful lean you may need to address carb and even that out, you should not fluctuate air foes that much from 1500-6000 I am high 11's to 12.4 the whole time.
buddy did builds with 502's, edelbrock ZZ502 heads fully ported, 238/246 cam and 850 carbs did 621HP you can make nice numbers if you chose parts right.
#26
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Joined: Sep 2015
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All the info has been great there is a bigger issue that I need to solve motor is not getting enough air in the bilge for motor
had to open and modify side scoops figured it out when I was at crus speed cracked the hatch about an inch and the motor leaned out motor fun fun
had to open and modify side scoops figured it out when I was at crus speed cracked the hatch about an inch and the motor leaned out motor fun fun
#27
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Joined: Oct 2007
Posts: 8,439
Likes: 93
From: yorkville,il
only real advantage of having aluminum over iron heads is the ability to fix them if something happens and ease of porting as aluminum is softer.
650-690 hp? the most I see in a 509 N/A would be 620-630 unless you really have a perfect parts selection, I would not go more then 310CC runner and do not buy heads done unless they are done by the shop putting engine together, always buy bare and have the builder make heads right.some shops will charge big money and end up faking up the heads.
14:1 at cruise? that's awful lean you may need to address carb and even that out, you should not fluctuate air foes that much from 1500-6000 I am high 11's to 12.4 the whole time.
buddy did builds with 502's, edelbrock ZZ502 heads fully ported, 238/246 cam and 850 carbs did 621HP you can make nice numbers if you chose parts right.
650-690 hp? the most I see in a 509 N/A would be 620-630 unless you really have a perfect parts selection, I would not go more then 310CC runner and do not buy heads done unless they are done by the shop putting engine together, always buy bare and have the builder make heads right.some shops will charge big money and end up faking up the heads.
14:1 at cruise? that's awful lean you may need to address carb and even that out, you should not fluctuate air foes that much from 1500-6000 I am high 11's to 12.4 the whole time.
buddy did builds with 502's, edelbrock ZZ502 heads fully ported, 238/246 cam and 850 carbs did 621HP you can make nice numbers if you chose parts right.
Last edited by mike tkach; 07-19-2017 at 08:23 AM.
#29
after my issue is enough to buy bare, and when I had my issues nearly every single builder said to never buy assembled dads... I was told that before also but ignored that advice and it didn't help my situation at all, let's say the guides are fine... still had solid Roller springs on one of my sets if I kept running them I would have had even more issues, I know the next comment is...."take them apart and have guides re honed to size, and check and change valve springs... at that point your into the heads more money assembled then if you built them from bare, not sure anyone can say otherwise
#30
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Joined: Oct 2007
Posts: 8,439
Likes: 93
From: yorkville,il
afr 320,when did afr start selling a 320 head?i know they sell a 315 cnc head and an as cast 325 head.



